Kosmos (Russian: Ко́смос, IPA: [ˈkozməs], Cosmos) is a designation given to a large number of satellites operated by the Soviet Union and subsequently Russia. Kosmos 1, the first spacecraft to be given a Kosmos designation, was launched on March 16, 1962.

As of September 2010, 2,468 Kosmos satellites had been launched. The spacecraft do not form a single programme, but instead consist of almost all Soviet and Russian military satellites, as well as a number of scientific satellites, and spacecraft which failed during or immediately after launch, but still reached orbit. Control systems for 152 spacecraft which were later assigned Kosmos designations were developed and manufactured by NPO Electropribor (Kharkiv).[1]

The designation is given only to satellites which are in Earth orbit. Typically, Soviet Lunar and planetary missions were initially put into an low Earth parking orbit along with an upper stage, which would later burn for around four minutes to place the spacecraft into a cislunar or a heliocentric orbit. If the engine misfired or the burn was not completed, the probes which would be left in Earth orbit would be given a Kosmos designation.

Most Soviet and subsequently Russian military satellites were given Kosmos designations. Spacecraft include optical reconnaissance satellites, communications satellites, early warning missile defence spacecraft, nuclear-powered radar reconnaissance satellites, anti-satellite weapons and their targets, navigation satellites and technology demonstrators. Some scientific spacecraft such as Dnepropetrovsk Sputnik, Bion and Meteor satellites were also given Kosmos designations.